I think they are mawkish and almost bring out an element of rubbernecking in people; but I can also see where there is a sudden death, they provide the opportunity for people to respond in an immediate way. Grief is private, but when young lives are involved, how do classmates/ friends come to terms with losing someone. I think many people find themselves already prepared/ expectant when they lose a loved one - but that's not the case in roadside deaths. And a simple act of leaving a message in a significant place perhaps offers a ritual that can be helpful. But I agree they need to be taken down within a certain period - a month at the very most. Leaving flowers to rot and die with tattered bits of paper, where one can no longer even make out a message, just re-inforces the bleakness of the event in my opinion. What I personally can't stand is public grieving over strangers - the Dianas and the Jacksons of the world.